Bug 663803 - Add hitCluster flag to detect touch in cluster links area r=smaug,kats

dom/events/MouseEvent.cpp

@@ -466,6 +466,12 @@ MouseEvent::GetMozPressure(float* aPressure)
   return NS_OK;
 }
 
+bool
+MouseEvent::HitCluster() const
+{
+  return mEvent->AsMouseEventBase()->hitCluster;
+}
+
 uint16_t
 MouseEvent::MozInputSource() const
 {

dom/events/MouseEvent.h

@@ -83,6 +83,7 @@ public:
     return GetMovementPoint().y;
   }
   float MozPressure() const;
+  bool HitCluster() const;
   uint16_t MozInputSource() const;
   void InitNSMouseEvent(const nsAString& aType,
                         bool aCanBubble, bool aCancelable,

dom/webidl/MouseEvent.webidl

@@ -106,6 +106,8 @@ partial interface MouseEvent
                                        EventTarget? relatedTargetArg,
                                        float pressure,
                                        unsigned short inputSourceArg);
+  [ChromeOnly]
+  readonly attribute boolean hitCluster; // True when touch occurs in a cluster of links
 
 };
 

layout/base/PositionedEventTargeting.cpp

@@ -75,6 +75,7 @@ struct EventRadiusPrefs
   bool mRegistered;
   bool mTouchOnly;
   bool mRepositionEventCoords;
+  bool mTouchClusterDetection;
 };
 
 static EventRadiusPrefs sMouseEventRadiusPrefs;
@@ -121,6 +122,9 @@ GetPrefsFor(EventClassID aEventClassID)
 
     nsPrintfCString repositionPref("ui.%s.radius.reposition", prefBranch);
     Preferences::AddBoolVarCache(&prefs->mRepositionEventCoords, repositionPref.get(), false);
+
+    nsPrintfCString touchClusterPref("ui.zoomedview.enabled", prefBranch);
+    Preferences::AddBoolVarCache(&prefs->mTouchClusterDetection, touchClusterPref.get(), false);
   }
 
   return prefs;
@@ -316,7 +320,8 @@ SubtractFromExposedRegion(nsRegion* aExposedRegion, const nsRegion& aRegion)
 static nsIFrame*
 GetClosest(nsIFrame* aRoot, const nsPoint& aPointRelativeToRootFrame,
            const nsRect& aTargetRect, const EventRadiusPrefs* aPrefs,
-           nsIFrame* aRestrictToDescendants, nsTArray<nsIFrame*>& aCandidates)
+           nsIFrame* aRestrictToDescendants, nsTArray<nsIFrame*>& aCandidates,
+           int32_t* aElementsInCluster)
 {
   nsIFrame* bestTarget = nullptr;
   // Lower is better; distance is in appunits
@@ -358,6 +363,8 @@ GetClosest(nsIFrame* aRoot, const nsPoint& aPointRelativeToRootFrame,
       continue;
     }
 
+    (*aElementsInCluster)++;
+
     // distance is in appunits
     float distance = ComputeDistanceFromRegion(aPointRelativeToRootFrame, region);
     nsIContent* content = f->GetContent();
@@ -424,10 +431,18 @@ FindFrameTargetedByInputEvent(WidgetGUIEvent* aEvent,
     return target;
   }
 
+  int32_t elementsInCluster = 0;
+
   nsIFrame* closestClickable =
     GetClosest(aRootFrame, aPointRelativeToRootFrame, targetRect, prefs,
-               restrictToDescendants, candidates);
+               restrictToDescendants, candidates, &elementsInCluster);
   if (closestClickable) {
+    if (prefs->mTouchClusterDetection && elementsInCluster > 1) {
+      if (aEvent->mClass == eMouseEventClass) {
+        WidgetMouseEventBase* mouseEventBase = aEvent->AsMouseEventBase();
+        mouseEventBase->hitCluster = true;
+      }
+    }
     target = closestClickable;
   }
   PET_LOG("Final target is %p\n", target);

mobile/android/app/mobile.js

@@ -395,6 +395,8 @@ pref("font.size.inflation.minTwips", 120);
 // When true, zooming will be enabled on all sites, even ones that declare user-scalable=no.
 pref("browser.ui.zoom.force-user-scalable", false);
 
+pref("ui.zoomedview.enabled", false);
+
 pref("ui.touch.radius.enabled", false);
 pref("ui.touch.radius.leftmm", 3);
 pref("ui.touch.radius.topmm", 5);

mobile/android/chrome/content/browser.js

@@ -4980,7 +4980,7 @@ var BrowserEventHandler = {
     if (!target) {
       return;
     }
-
+    this._inCluster = aEvent.hitCluster;
     let uri = this._getLinkURI(target);
     if (uri) {
       try {
@@ -5095,16 +5095,18 @@ var BrowserEventHandler = {
           Cu.reportError(e);
         }
 
-        // The _highlightElement was chosen after fluffing the touch events
-        // that led to this SingleTap, so by fluffing the mouse events, they
-        // should find the same target since we fluff them again below.
         let data = JSON.parse(aData);
         let {x, y} = data;
-
-        this._sendMouseEvent("mousemove", x, y);
-        this._sendMouseEvent("mousedown", x, y);
-        this._sendMouseEvent("mouseup",   x, y);
-
+        if (this._inCluster) {
+          this._clusterClicked(x, y);
+        } else {
+          // The _highlightElement was chosen after fluffing the touch events
+          // that led to this SingleTap, so by fluffing the mouse events, they
+          // should find the same target since we fluff them again below.
+          this._sendMouseEvent("mousemove", x, y);
+          this._sendMouseEvent("mousedown", x, y);
+          this._sendMouseEvent("mouseup",   x, y);
+        }
         // scrollToFocusedInput does its own checks to find out if an element should be zoomed into
         BrowserApp.scrollToFocusedInput(BrowserApp.selectedBrowser);
 
@@ -5127,6 +5129,16 @@ var BrowserEventHandler = {
     }
   },
 
+  _clusterClicked: function sh_clusterClicked(aX, aY) {
+      Messaging.sendRequest({
+        type: "Gesture:clusteredLinksClicked",
+        clicPosition: {
+          x: aX,
+          y: aY
+        }
+      });
+  },
+
   onDoubleTap: function(aData) {
     let metadata = BrowserApp.selectedTab.metadata;
     if (!metadata.allowDoubleTapZoom) {

widget/MouseEvents.h

@@ -83,6 +83,7 @@ protected:
     , button(0)
     , buttons(0)
     , pressure(0)
+    , hitCluster(false)
     , inputSource(nsIDOMMouseEvent::MOZ_SOURCE_MOUSE)
  {
  }
@@ -127,6 +128,8 @@ public:
 
   // Finger or touch pressure of event. It ranges between 0.0 and 1.0.
   float pressure;
+  // Touch near a cluster of links (true)
+  bool hitCluster;
 
   // Possible values at nsIDOMMouseEvent
   uint16_t inputSource;
@@ -143,6 +146,7 @@ public:
     button = aEvent.button;
     buttons = aEvent.buttons;
     pressure = aEvent.pressure;
+    hitCluster = aEvent.hitCluster;
     inputSource = aEvent.inputSource;
   }